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GRATIS-BAR FOR FURNACE. l

sPEcIFgcCATIoN'. TO ALL WHOM IT MAY CONCERN; i L

Be it known'that I, CHARLES C. BEMIS, of San Francisco, San Francisco county, State of California, have invented certain new and useful improvements in Grate Bars for Furnaces; and I do hereby declare the following description and accompanying drawings are sufiicient t'o enable any person, skilled in the art orlscience to` which it most nearly appertains, to make and use my said invention, withodtlfurther invention or experiment. The nature of my invention is to provide a furnace having a grate-bar in which a more eiicient draught may be maintainedthrough the fire, and the air have a greater space to pass through, and be deflected more evenly' or profusely in the fire chamber before escaping to the chimney-flue. In order to accomplish this object, and

present a check or barrier to the air, I place intercepting plates of different depths along beneath the grate. Referring to the drawings- Figure 1 represents a side sectional elevation of my grate-bar.'

vFigure 2, a plan. n

a a represent the grate surface extending beneath the boiler, with the bars placed lengthwise and transversely alternately. Commencing at the forward portion of the grate, at regular intervals between the longitudinal and transverse sections, I place bridges or barrier plates, b, c, d, e, f, each one farther back extending a little below the preceding one. By this arrangement, the current'of air as it passes beneath the grate is partly intercepted and divided at b, a portion being carried'up into the fuel, and a portion passing around the lower edge of the plate or barrier into the next section, and `again dellected by c, and so on by each plate, iii an increasing degree of deflection or resistance according to the depth of the plates beneath the grate-bars, thus causing the air or draught to be distributed overthe entire grate, instead of all rushing to the b ack of. the furnace as in other devices for grates where no intercepting "plates are employed. Also by the use of my grate a more even and effective combustion of the fuel is had, preventing the air from escaping up the ue before it `has imparted its greatest e'ect upon the fuel.

Havingthus describedmy invention, what I claim and desire to secureby Letters Patent, isf y A furnace grate with bridges or barrier plates, b, c, d, e, f, placed beneath the said grate at intervals, and,

increasing in depth to near the flue, the whole arranged and constructed substantially as described, and for the -purposerset forth. i

In witness whereof I have hereunto set my hand and seal this tenth day of August, 1866.

` CHAS C. BEMIS. 5.]

Witnesses:

C. W. M. SMITH, W. W. HANscoM. 

